CM Plugins on "[Plugin: CM Tooltip Glossary] feature image for glossary term"

I was using another glossary plugin before using yours, and i was able to put a feature image for my glossary terms.
All my terms that were recorded with my older plugin, are working well in your glossary, and all my feature images are displayed correctly.
Unfortunately, I don't see the option in the edit page of your plugin. I can't remove/change feature image anymore. Is there a way to put a feature image ?

https://wordpress.org/plugins/enhanced-tooltipglossary/

Hi,

Unfortunately Featured Image is not one of the free features.
Sorry.

Best,
CM Plugins